Since its foundation in 1975, The American Society of Andrology has been predicated upon the importance of linking basic science, clinical practice and public health in an interdisciplinary manner. Accordingly, the annual meeting, of which there have been 30, is structured to attract attendees from a variety of areas related to male reproductive health and to foster interaction among them through an integrated scientific program. Because it is a relatively small meeting, typically having 250 to 350 attendees, the plenary sessions are planned to be inclusive with a "bench to bedside" approach so that all attendees, regardless of individual research interests, will want to attend all sessions. This practice results in valuable interactions among clinicians in several disciplines (Urology, Andrology, Endocrinology, Infertility, Reproductive Tract Cancer), basic scientists studying male reproduction (e.g., cell and molecular biology of spermatogenesis and fertilization, reproductive organ and tract development, mechanisms of endocrine action, reproductive genetics, physiology of reproduction and sexual function), and Andrology laboratory staff working on the diagnosis and treatment of infertility. The 2006 (31st) Annual Meeting, scheduled for April 8-11 in Chicago, IL, will continue in this fine tradition with the main program theme of "Contemporary Dimensions of Male Reproductive Physiology and Health," over 2.5 days, and a structure consisting of plenary 1-hour lectures, symposia (3 half-hour talks), short 15-minute talks from selected abstracts, and poster sessions. Topics are designed to bring participants up to date with the latest research findings in the molecular biology of fertilization and nuclear reprogramming in the zygote (including advances in stem cell biology and gene regulation during sexual determination and differentiation), the genetic regulation of prostate and testes development, discovery of new genes involved in male reproduction (with applications in toxicology, contraceptive development, and treatment of male infertility), the endocrine bases for fertility and infertility, including early exposure to anti-androgens in the environment, and the scientific basis for treatment of erectile dysfunction. A 1-day postgraduate course for 2006 will address "Issues in Male Sexual Health: From Benchmark to Bedside" with a focus on physiology and treatment of sexual dysfunction, and a 1-day "hands- on" Andrology Lab Workshop on semen analysis with a focus on sperm motility evaluation.